Composite pane for a glazing which can be illuminated three-dimensionally

Abstract

The invention relates to a pane (100) for an illuminable glazing (101), at least comprising – an outer pane (1), - a first panel-shaped optical waveguide (2.1) with at least one output coupling element (4) for coupling out light (5), and a second panel-shaped optical waveguide (2.2) with at least one output coupling element (4) for coupling out light (5), wherein between the outer pane (1) and the first optical waveguide (2.1) is a first thermoplastic intermediate layer (3.1), and between the first optical waveguide (2.1) and the second optical waveguide (2.2) is a second thermoplastic intermediate layer (3.2), the first optical waveguide (2.1) and the second optical waveguide (2.2) each having a thickness of maximally 700 µm.

Description

[0001] Composite pane for three-dimensionally illuminated glazing

[0002] The invention relates to a laminated pane for an illuminable glazing and to a glazing with such a laminated pane.

[0003] Illuminated glazing elements are well known. They are equipped with a light source whose light is coupled into an optical fiber, usually a glass pane, and spreads through total internal reflection. Often, the light is extracted from the optical fiber by extraction elements, thus creating the illumination. The shape of the extraction elements is freely selectable, allowing illuminated surfaces of any shape, for example, a pattern, to be created. Illuminated glazing elements of this type are known, for example, from WO2014 / 060409A1 or WO2014 / 167291A1.

[0004] In the automotive sector, such illuminated glazing elements are particularly interesting for roof windows. The glazing element is typically designed as a composite pane, with the light coupled into the inner pane. However, such illuminated glazing elements can also be used for other vehicle windows, as well as for windows in buildings and architecture, or in furnishings. The coupling elements create illuminated surfaces that can be used to display aesthetically pleasing shapes and patterns or to display information, for example, directional arrows, status indicators, warning notices, price lists, or similar.

[0005] There are various known ways to couple the light from the light source into the optical waveguide formed as a glass pane. The light source (typically an LED) can be positioned at the side edge, so that the light is radiated into the glass pane via the side edge and thus coupled into it. However, such coupling is often impossible, particularly because the side edge of the glass pane is usually ground to increase the mechanical stability of the pane, which causes the side edge to become cloudy.

[0006] In many cases, however, illuminated glazing elements feature a large number of light extraction elements or large light extraction areas. If the light is coupled in at the edge of the optical fiber, as is usually the case, this leads to a gradual attenuation of the light extraction intensity towards the center of the extraction element. This attenuation is due to the fact that the amount of light coupled in towards the extraction center decreases as the light extraction progresses. This, in turn, leads to the edge areas of the extraction element closest to the light source being very brightly illuminated, whereas the central areas are less illuminated. For a user, this can give the impression that the glazing is not functioning properly. It also reduces the aesthetics of the glazing when illuminated.

[0007] WO2022216556A2 discloses a composite pane for vehicles or buildings, in which several optical fiber core layers are laminated between an outer pane and an inner pane. The optical fiber core layers are separated from one another by a cladding layer, preferably one with a low refractive index. The cladding layer, like the optical fiber core layers, is made of a polymer or glass, resulting in the core conductor layers being arranged relatively rigidly within the composite pane.

[0008] The present invention is based on the object of providing an improved pane for illuminable glazing that can be illuminated more effectively across the entire surface of the pane, has improved stability, and can also be illuminated with higher optical quality. The present invention is also based on the object of providing glazing with such a pane.

[0009] The object of the present invention is achieved by a pane according to claim 1 and an illuminable glazing according to claim 12. Preferred embodiments emerge from the subclaims.

[0010] The composite pane according to the invention for illuminable glazing comprises at least one outer pane, a first plate-shaped optical waveguide, and a second plate-shaped optical waveguide. A first thermoplastic intermediate layer is arranged between the outer pane and the first optical waveguide. A second thermoplastic intermediate layer is arranged between the first optical waveguide and the second optical waveguide. The thermoplastic intermediate layers serve to connect the outer pane and the optical waveguides to one another. The intermediate layers are arranged flatly between the outer pane and the optical waveguides. The outer pane has an outer surface facing away from the first thermoplastic intermediate layer and an interior surface facing the first thermoplastic intermediate layer.Each optical waveguide has an outer surface facing the outer pane and an inner surface facing away from the outer pane. The first thermoplastic intermediate layer is thus arranged on the inner surface of the outer pane and the outer surface of the first optical waveguide. The second thermoplastic intermediate layer is thus arranged on the inner surface of the first optical waveguide and on the outer surface of the second optical waveguide. The inner surface and outer surface of an optical waveguide refer to the main surfaces of the optical waveguide.

[0011] If the composite pane does not have any further plate-shaped optical fibers, the second optical fiber is the inner pane of the composite pane. The composite pane can also have further plate-shaped optical fibers, for example one, two or three further optical fibers. These further optical fibers are arranged one above the other, starting from the second optical fiber, with at least one thermoplastic intermediate layer always being arranged between two optical fibers. The order in which the optical fibers are arranged on the second optical fiber follows a numerical order, so that the inner pane is always formed by the optical fiber with the highest numerical position. In other words: if the composite pane comprises a total of four plate-shaped optical fibers, the fourth optical fiber is the inner pane of the composite pane.For the purposes of the invention, "inner pane" refers to the optical fiber closest to the interior (e.g., the vehicle interior). For the purposes of the invention, "outer pane" refers to the pane closest to the exterior environment. However, the invention is not limited to this. The interior-facing surface of the inner pane is also the interior-facing surface of the composite pane. The exterior-facing surface of the outer pane is also the exterior-facing surface of the composite pane. The composite pane can be flat or curved in one or more spatial directions.

[0012] Unless otherwise stated, all elements of the laminated pane mentioned here, which are arranged between the outer pane and the inner pane, are arranged "flat" or "flatly superimposed." In other words, the main surfaces of these elements are arranged essentially parallel to the surfaces of the outer pane and the inner pane. The "thickness" or "layer thickness" of an element refers to the dimension essentially orthogonal to the main surface of the element. The main surface of the element describes the surface of the element with the greatest extent.

[0013] According to the invention, the first optical waveguide has at least one coupling element for coupling out light, and the second optical waveguide has at least one coupling element for coupling out light. The first optical waveguide has a thickness of at most 700 pm, and the second optical waveguide also has a thickness of at most 700 pm.

[0014] For the purposes of the invention, "plate-shaped optical waveguide" means that the optical waveguide is designed in the shape of a plate. Plate-shaped optical waveguides are therefore significantly larger in two dimensions than in the third dimension (thickness of the optical waveguide). Plate-shaped also means that the optical waveguides can serve as support elements, i.e., they are not coatings or liquids. The plate-shaped optical waveguides are preferably designed as glass plates, although the term "glass plate" can also refer to plates made of polymeric materials (e.g., Plexiglas plates).

[0015] The optical waveguides are intended to guide light that is coupled into them. In the context of the invention, "optical waveguide" means a light-conducting medium that is designed such that light can be coupled into the optical waveguide using the effect of total internal reflection, and is also suitable for guiding coupled-in light. The principle of light guidance using total internal reflection is generally known to those skilled in the art and is described in more detail, for example, in WO2008 / 047442A1, JP2011086547A or JP2015043321A. The optical waveguide is therefore designed such that the light from a light source can be coupled into the optical waveguide and propagate therein. The outcoupling elements serve to specifically couple the coupled-in light out of the optical waveguide.

[0016] When reference is made to "the optical waveguides," this refers, unless explicitly stated otherwise, to all plate-shaped optical waveguides of the composite pane. "The optical waveguides" therefore refer to the first plate-shaped optical waveguide and the second plate-shaped optical waveguide, as well as, if present, the additional plate-shaped optical waveguides (e.g., a third optical waveguide, a fourth optical waveguide, and / or a fifth optical waveguide) of the composite pane according to the invention. When reference is made to "the thermoplastic intermediate layers," this refers, unless explicitly stated otherwise, to all thermoplastic intermediate layers of the composite pane.“Thermoplastic intermediate layers” therefore refers to at least the first thermoplastic intermediate layer and the second thermoplastic intermediate layer and, if present, also the further thermoplastic intermediate layers (for example a third thermoplastic intermediate layer, a fourth thermoplastic intermediate layer and / or a fifth thermoplastic intermediate layer) of the composite pane according to the invention.

[0017] The invention is based on the fact that visible light can be coupled into various optical waveguides of the composite pane. By stacking the optical waveguides and separating them by at least one thermoplastic intermediate layer, the light is largely prevented from being unintentionally coupled out of the optical waveguides, thus avoiding undesired light loss in the optical waveguides. A further advantage achieved by the invention is that the coupling-out element of the first optical waveguide is located at a different height or on a different plane of the composite pane than the coupling-out element of the second optical waveguide. The coupling-out elements are therefore arranged at different locations, measured perpendicular to the main surface of the composite pane.This results in three-dimensional illumination of the composite pane when light is coupled into the optical fibers and then extracted, increasing the quality of the illumination depending on the intended use. A further advantage is that the extraction elements in the various optical fibers can be illuminated with light of different colors. This makes it possible to create extraction regions with different colors. In particular, the light is distributed more evenly across the entire surface of the composite pane, since the extraction elements of the individual optical fibers only need to cover small areas of the surface, thus overcoming the disadvantages described in the prior art. The low thickness of the plate-shaped optical fibers prevents the composite pane from becoming too heavy and unstable.It also enables a compact design, which is particularly advantageous in confined spaces such as those found in modern vehicles. The use of a thermoplastic intermediate layer between the optical fibers also improves the adhesion of the individual elements within the composite pane, thus contributing to overall stability. The thermoplastic intermediate layer provides a flexible yet robust connection that is resistant to mechanical stress without excessively reducing unwanted light loss. These findings were unexpected and surprising to the inventors. In a preferred embodiment of the invention, the second optical fiber and the second thermoplastic intermediate layer extend over the entire surface of the first optical fiber with the exception of a first partial region.This has the advantage that a light source intended to couple light into the first optical waveguide can be arranged on the interior surface of the first optical waveguide. It therefore does not have to be arranged between the first optical waveguide and the outer pane within the first thermoplastic intermediate layer, or between the first optical waveguide and the second optical waveguide within the second thermoplastic intermediate layer. This allows greater flexibility in the size and shape of the light source.

[0018] The thickness of the outer pane is preferably from 0.5 mm to 10 mm, particularly preferably from 1 mm to 5 mm. The thermoplastic intermediate layers can each comprise one or more thermoplastic composite films. Each thermoplastic intermediate layer preferably has a thickness of, for example, 0.3 mm to 1.0 mm (sum of the thicknesses of all films of the intermediate layer). The intermediate layer is particularly preferably made of polyvinyl butyral (PVB), ethylene-vinyl acetate (EVA), polyester or polyurethane (PU). Particularly preferably, at least the first thermoplastic intermediate layer and the second thermoplastic intermediate layer are based on polyvinyl butyral, polyurethane, polyvinyl acetate or polyester, preferably polyvinyl butyral. This means that all thermoplastic films are preferably based on these materials. Furthermore, the films orThe entire intermediate layer may contain additional components, such as plasticizers, stabilizers, UV or IR blockers. The thermoplastic intermediate layers may be clear or tinted independently of one another. Preferably, only the first thermoplastic intermediate layer is tinted and has a light transmittance (according to ISO 9050:2003) of less than 70%, preferably less than 50%, particularly preferably less than 30%. In particular, the first thermoplastic intermediate layer has a light transmittance (according to ISO 9050:2003) of a maximum of 30%, preferably a maximum of 10%. This effectively prevents light from the optical fibers from being emitted via the outer pane into the external environment.

[0019] Preferably, at least the first optical waveguide and / or the second optical waveguide each have a thickness of at most 500 μm, preferably from 200 μm to 500 μm. This thickness improves the mechanical stability of the composite pane and ensures stable adhesion within the composite pane. Particularly preferably, all optical waveguides each have a thickness of at most 500 μm, preferably from 200 μm to 500 μm. This thickness range is particularly suitable when multiple optical waveguides are laminated together.

[0020] The outer pane, the first optical waveguide, the second optical waveguide and / or any additional optical waveguides that may be present are preferably made of soda-lime glass, as is common for window panes. Alternatively, they can also be made of other types of glass, for example borosilicate glass, aluminosilicate glass or quartz glass. It is also possible for the outer pane and / or the optical waveguides to be designed as plastic panes. If the outer pane and / or all or individual optical waveguides are designed as a plastic pane, these are preferably made of a clear, rigid plastic, particularly preferably polycarbonate (PC) or polymethyl methacrylate (PMMA). In a preferred embodiment, at least the first optical waveguide and the second optical waveguide are made from soda-lime glass, polycarbonate or polymethyl methacrylate.

[0021] The outer pane and / or the optical waveguide serving as the inner pane may have other suitable layers known per se, for example anti-reflective coatings, non-stick coatings, anti-scratch coatings, photocatalytic coatings or sun protection coatings or low-E coatings.

[0022] In a preferred embodiment of the invention, the outer pane is tinted and has a light transmittance (according to ISO 9050:2003) of less than 70%, preferably less than 50%, particularly preferably less than 30%. Alternatively, the outer pane can also be clear and have a light transmittance of greater than or equal to 70%. The tinting of the outer pane improves the light-absorbing properties of the laminated pane. If light is coupled out toward the outer pane by one of the optical fibers, the tint prevents the light from propagating through the outer pane into the external environment. This may be necessary, for example, when the laminated pane is used in vehicles.

[0023] The interior surface and the exterior surface of a plate-shaped optical waveguide represent interfaces to the adjacent medium. The exterior surface of a plate-shaped optical waveguide is, for example, the interface to a thermoplastic intermediate layer or to a low-refractive-index coating. The interior surface of a plate-shaped optical waveguide is, for example, the interface to the surrounding atmosphere or to a low-refractive-index coating. Typically, the media adjacent to the surfaces of the optical waveguide (for example, the interior atmosphere or the low-refractive-index layer) have a different refractive index than the optical waveguide. In the case that the adjacent medium has a different refractive index than the optical waveguide, this results in a critical angle of total internal reflection, which is determined as a T= arcsin(— ), where ni is the refractive index of the optically denser medium and n2 is the refractive index of the optically rarefying medium. In the case of the interface between an optical fiber and air, the refractive index of the optical fiber is m and the refractive index of the air is n2. If light hits the interface at an angle of incidence that is greater than the critical angle, the light is completely reflected (total internal reflection). As is common in ray optics, the angle of incidence is the angle that the light ray incident on the surface makes to the surface normal at the point of impact. The angle of reflection is determined analogously to the surface normal, as is the critical angle of total internal reflection. Even small differences in the refractive indices are sufficient to make light transmission by means of total internal reflection, whereby the light loss increases with the difference between the refractive indices.

[0024] The composite pane is intended to separate an interior space from the exterior environment in a window opening of a vehicle or building. The composite pane is preferably a vehicle window composite pane, in particular a vehicle roof pane.

[0025] In a preferred embodiment of the invention, a low-refractive-index coating is applied at least to the interior-side surface or the exterior-side surface, alternatively to both the interior-side surface and the exterior-side surface, of the first plate-shaped optical waveguide. Alternatively or additionally, a low-refractive-index coating is preferably applied at least to the interior-side surface or the exterior-side surface, alternatively to both the interior-side surface and the exterior-side surface, of the second plate-shaped optical waveguide. In particular, all optical waveguides have a low-refractive-index coating on at least one of their main surfaces, preferably all of their main surfaces, wherein the interior-side surface of the optical waveguide serving as the inner pane is preferably free of the low-refractive-index coating.The refractive index of the low-index coating is at least 0.05 lower than the refractive index of the optical fiber to which it is applied. Due to the lower refractive index of the low-index coating, the resulting critical angle is smaller, thereby expanding the angular range over which light propagates under total internal reflection.

[0026] Refractive indices are generally given in the context of the present invention relative to a wavelength of 550 nm. Methods for determining refractive indices are known to those skilled in the art. The refractive indices given in the context of the invention can be determined, for example, by ellipsometry, whereby commercially available ellipsometers can be used. The specification of layer thicknesses or thicknesses refers, unless otherwise stated, to the geometric thickness of a layer.

[0027] A low-refractive-index coating preferably has a refractive index that is at least 0.1, more preferably at least 0.15, in particular at least 0.2, lower than the optical waveguide to which it is applied. Such refractive index differences are preferred because, as the difference increases, the critical angle at which total reflection is achieved becomes smaller. The refractive index of at least one low-refractive-index coating is preferably at most 1.5, more preferably at most 1.45, in particular at most 1.4. More preferably, all low-refractive-index coatings each have such a refractive index. Most preferably, all low-refractive-index coatings have the same refractive index, where “same refractive index” means that the refractive indices may differ by a maximum of 0.01.

[0028] Low-refractive-index coatings can be formed, for example, as an organic, cross-linked, or thermoplastic polymer. Alternatively, the low-refractive-index coating can also be a mineral layer.

[0029] In a preferred embodiment of the invention, at least one low-refractive-index coating, preferably all low-refractive-index coatings, is formed as a lacquer, which can be obtained from a photocrosslinkable resin, optionally mixed with photoinitiators. Alternatively, the resin is thermally crosslinkable. It can, for example, be formed from a two-component mixture.

[0030] In particular, at least one of the low-refractive-index coatings, preferably all low-refractive-index coatings, comprises or consists of a cross-linked polymer matrix with a refractive index of at most 1.42, preferably at most 1.40, in particular at most 1.3, wherein the matrix is ​​preferably formed from polymers based on polyacrylate, particularly preferably based on fluorine-functionalized polyacrylate. The refractive index of the low-refractive-index coating can be reduced by means of fluorine functionalization. The use of polyacrylate as a material for the low-refractive-index coating is advantageous because acrylate compounds can be efficiently cross-linked by photopolymerization, thereby simplifying the production of the low-refractive-index coatings. In particular, the polymer matrix is ​​formed from urethane acrylate or fluorourethane acrylate or fluorosilicone acrylate.Alternatively, the polymer matrix can also be based on silicone, polydimethylsiloxane, epoxy polymer, polyvinyl butyral, polyepoxides, polyurethane, polyvinyl acetate, or polyester. Preferably, at least one low-refractive-index coating, and preferably all low-refractive-index coatings, contain no free silicone or silicon compounds (a source of surface contamination). Any silicone or silicon compounds present are therefore an integral part of the polymer matrix and are not removed from the low-refractive-index coating, for example, in a deaeration process during lamination (if the pane is designed as a composite pane).

[0031] For the purposes of the invention, "polyacrylate" refers to a polymer containing repeating units of acrylic compounds, i.e., whose monomers belong to the acrylic group. The repeating unit can be substituted or unsubstituted within the permissible valence range. The polyacrylate can be a homopolymer or a copolymer, i.e., composed of only one type of monomer or of several different types of monomers. In particular, "polyacrylate" refers to polymers such as polymethylacrylate, polyethyleneacrylate, polypropylmethacrylate, polymethylmethacrylate, polyethylenemethacrylate, polyethylmethacrylate, or polypropylmethacrylate. Polyacrylate can also refer to mixtures of such polymers.

[0032] For the purposes of the invention, "epoxy polymer" means that the polymer contains epoxy compounds. The epoxy polymer preferably comprises one or more compounds from the group consisting of bisphenol A epoxy resins, halogenated phenol epoxy resins, phenol epoxy resins, cycloaliphatic epoxy resins, and bisphenol S epoxy resins, particularly preferably in a proportion of at least 1 wt.%, in particular at least 5 wt.%.

[0033] Low-refractive index coatings can be achieved particularly by

[0034] • Flow coating, • Dip coating,

[0035] • Screen printing,

[0036] • Digital printing or

[0037] • Inkjet printing. The application can be done by rotation coating, film puller 1, curtain or slot die coating, Meyer bar printing or gravure printing. The low-refractive index coatings are preferably applied as a UV-photocrosslinkable substrate and then polymerized using UV radiation. Alternatively, it is also possible to apply two components which react with each other spontaneously (exergonic reaction) or under the influence of heat (endergonic). This is a two-component formulation which crosslinks to form a polymer through a chemical reaction. Crosslinking using UV radiation is preferred because the crosslinking is faster and the process is more cost-effective / compact than with a chemical reaction. In particular, components are used which polymerize under the influence of UVA radiation (wavelength range from 315 nm to 405 nm).

[0038] In a preferred embodiment, at least one low-refractive-index coating, preferably all low-refractive-index coatings, contains a polymer that can be produced by photopolymerization, particularly preferably photopolymerization initiated by UV radiation. The low-refractive-index coatings are preferably based on a polyacrylate (e.g., a urethane acrylate resin) or a silicone compound.

[0039] In a preferred embodiment of the invention, the low-refractive-index coating contains or consists of silicon oxide. Particularly preferably, at least one low-refractive-index coating, preferably all low-refractive-index coatings, comprises (nano-)porosities and / or (nano-)particles with a refractive index of less than or equal to 1.3. The porosities and / or particles are preferably hollow and have a diameter of at most 300 nm or in particular at most 100 nm. Particularly preferably, at least one low-refractive-index coating, preferably all low-refractive-index coatings, comprises hollow silicon dioxide nanoparticles. Preferably, the low-refractive-index coatings do not contain free silicone, volatile silicon compounds (source of surface contamination). The low-refractive-index coatings preferably have at most 60 vol.%, particularly preferably at most 50 vol.%, very particularly preferably at most 40 vol.%, in particular at most 30 vol.-% (nano-)porosities and / or (nano-)particles with a refractive index of less than or equal to 1.3.

[0040] In a particularly preferred embodiment of the invention, the low-refractive-index coatings comprise a polyacrylate polymer matrix, with silicon dioxide-based particles embedded in the polymer matrix. In particular, each of the low-refractive-index coatings consists of a polyacrylate polymer matrix, with silicon dioxide-based particles embedded in the polymer matrix. In this way, a refractive index of less than 1.4 can be efficiently achieved.

[0041] If a low-refractive-index coating is based on a mineral layer, it consists predominantly of the mineral layer, in particular essentially of this material in addition to any impurities or dopants.

[0042] The layer thickness of low-refractive-index coatings is preferably at most 10 pm mm, particularly preferably less than 5 pm, in particular less than 400 nm.

[0043] Low-refractive-index coatings can be applied by physical or chemical vapor deposition, i.e., PVD or CVD (physical vapor deposition, chemical vapor deposition), or, for example, using the sol-gel process. Such coatings can be produced with particularly high optical quality and a particularly thin thickness. The application of layers using the sol-gel process is known to those skilled in the art and can be found, for example, in WO2021209201 A1. The volume fraction of the pores of porous silicon dioxide can be limited and controlled by producing it using a sol-gel process.

[0044] A PVD coating can be a coating applied by cathode sputtering

[0045] (“sputtered”) coating, in particular a magnetic field-assisted

[0046] The coating can be applied by cathode sputtering (magnetron sputtering). Low-refractive-index coatings, such as a mineral layer (e.g., SiO2), are preferably applied by magnetron sputtering. Magnetron sputtering can efficiently create a homogeneous layer just a few micrometers thick.

[0047] Low-refractive-index coatings, if formed as mineral layer(s), can also be applied using chemical vapor deposition. In this case, this is preferably done using plasma-enhanced chemical vapor deposition (PECVD), particularly at atmospheric pressure (APCVD). The advantage of plasma-enhanced chemical vapor deposition is the speed of application combined with high layer homogeneity compared to other processes. Silicon oxide, in particular, can be applied homogeneously and efficiently to a substrate using this process.

[0048] However, low-refractive-index coatings can also be applied by other methods known to those skilled in the art, for example by wet-chemical methods, for example sol-gel processes, such as spray coating, dip coating, spin coating or casting.

[0049] Sol-gel processes generally refer to the condensation of colloidally dissolved particles into three-dimensional networks, with the colloids varying in size from 1 nm to several thousand nm. In spray coating, a sol is atomized by supplying a specific amount of air, and the sol is then transported to the substrate in very small particles. In dip coating, the substrate is immersed in a solution and then withdrawn at a constant speed. In the casting process, a synthesis solution is dripped onto the substrate and the solvent is waited for to evaporate. The production of coatings by casting is also based on the evaporation-induced self-assembly (EISA) mechanism. The films produced in this way can be significantly thicker than those produced by dip or spin coating.

[0050] The low-refractive-index coating preferably extends over at least 80%, particularly preferably at least 90%, of the main surface of the optical waveguide to which it is applied. In particular, the low-refractive-index coating extends over the entire main surface of the optical waveguide to which it is applied. In a very advantageous embodiment of the invention, the low-refractive-index coating extends over the entire main surface of the optical waveguide to which it is applied, minus a frame-shaped peripheral edge region of the optical waveguide. Thus, in a plan view of the pane, the low-refractive-index coating is framed by an area that is not provided with the low-refractive-index coating.

[0051] If the composite pane does not have any low-refractive-index coatings, the thermoplastic intermediate layers preferably have a refractive index that is at least 0.02 lower than the optical waveguides immediately adjacent to them. More preferably, the thermoplastic intermediate layers have a refractive index that is at least 0.05 lower, in particular at least 0.1 lower, than the optical waveguides immediately adjacent to them. The refractive index of the thermoplastic intermediate layers can be reduced, for example, by adding layers or portions of polyacrylate to the intermediate layer, particularly preferably layers or portions with fluorine-functionalized polyacrylate. In particular, the thermoplastic intermediate layers comprise portions or layers based on urethane acrylate or fluorourethane acrylate or fluorosilicone acrylate.Alternatively, the thermoplastic intermediate layers can also contain layers or portions of silicone, polydimethylsiloxane, epoxy polymer, polyvinyl butyral, polyepoxides, polyurethane, polyvinyl acetate, or polyester. Preferably, the thermoplastic intermediate layers do not contain free silicone or silicon compounds (a source of surface contamination).

[0052] In a further preferred embodiment, the composite pane also has a third plate-shaped optical waveguide which is connected flat to the second optical waveguide via a third thermoplastic intermediate layer. The third plate-shaped optical waveguide comprises at least one output coupling element for outputting light. Particularly preferably, the composite pane also comprises a fourth plate-shaped optical waveguide which is connected flat to the third optical waveguide via a fourth thermoplastic intermediate layer. The fourth plate-shaped optical waveguide comprises at least one output coupling element for outputting light. This number of optical waveguides leads to a visually very clearly perceptible three-dimensional illumination of the composite pane in a glazing. At the same time, with such a number of optical waveguides, the composite pane is still very stable, which is particularly important in the automotive sector.The composite pane can also comprise a fifth optical waveguide, which is bonded to the fourth optical waveguide via a fifth thermoplastic intermediate layer. This makes the three-dimensional illumination effect even more visually perceptible. The third optical waveguide, and, if present, the fourth optical waveguide and the fifth optical waveguide, have a maximum thickness of 700 pm.

[0053] In a particularly preferred embodiment of the invention building on the previous embodiment, the third optical waveguide and the third thermoplastic intermediate layer extend over the entire surface of the second optical waveguide with the exception of a second partial region. If the composite pane also comprises a fourth optical waveguide and a fourth thermoplastic intermediate layer, the fourth optical waveguide and the fourth thermoplastic intermediate layer particularly preferably extend over the entire surface of the third optical waveguide with the exception of a third partial region. If the composite pane also comprises a fifth optical waveguide and a fifth thermoplastic intermediate layer, the fifth optical waveguide and the fifth thermoplastic intermediate layer in particular extend over the entire surface of the fourth optical waveguide with the exception of a fourth partial region.This has the advantage that a light source intended to couple light into a deeper optical fiber can be positioned on the interior surface of the corresponding optical fiber. It therefore does not have to be positioned between two optical fibers within the corresponding thermoplastic intermediate layer. This allows greater flexibility in the size and shape of the light source.

[0054] Each of the (exposed) sub-regions of the optical waveguides (for example the first sub-region of the first optical waveguide, the second sub-region of the second optical waveguide, the third sub-region of the third optical waveguide, the fourth sub-region of the fourth optical waveguide) is intended to be arranged in relation to a light source such that the light from the light source can be coupled into the respective optical waveguide via the sub-region. Each sub-region is preferably arranged in an edge region of the composite pane according to the invention. Each of the sub-regions preferably extends by a maximum of 5%, particularly preferably by a maximum of 3%, in particular preferably by a maximum of 1%, over the area of ​​the composite pane. The area of ​​the composite pane is essentially defined by the area of ​​the outer pane.If one, several or all optical waveguides have low-refractive-index coatings, the low-refractive-index coatings are preferably not applied in the partial areas on the interior-side surface of the respective optical waveguide.

[0055] The outcoupling elements are suitable for coupling out a portion of the light guided into the pane according to the invention by scattering, reflection, refraction, or diffraction. The outcoupling elements can be incorporated within the optical waveguide or applied or arranged on the interior surface and / or on the exterior surface. The outcoupling elements are preferably formed by laser structuring, mechanical structuring such as sandblasting, and / or by etching. Alternatively or in combination, the outcoupling elements can be applied as prints on the interior surface and / or the exterior surface of the respective optical waveguide to which they belong. The print can contain an ink, a paste, and / or particles, particularly preferably light-scattering, light-refracting, or light-reflecting particles. The print can be transparent or opaque.In an advantageous embodiment, the coupling-out elements are transparent, so that they do not significantly restrict visibility through the laminated pane. The print (printing paste) therefore preferably contains no pigment. However, opaque or semi-transparent coupling-out elements with pigments are also conceivable, for example, white elements. The print can also produce a colored tint, i.e., at least not completely block visibility through the laminated pane, but lead to a tint in one or more areas of the laminated pane. The printing paste, if opaque, semi-transparent, or tinted, preferably contains dyes or color pigments.

[0056] Alternatively or in combination, the coupling elements can comprise or consist of particles, particularly preferably light-scattering, light-refracting, light-diffracting, or light-reflecting particles, scattering centers, or cavities arranged within the respective optical waveguide. Such scattering centers or cavities can be introduced into the layers, for example, by laser structuring.

[0057] The outcoupling elements of the optical fibers can also be applied as a foil or coated foil to the interior surface and / or the exterior surface of the respective optical fiber to which they belong. For example, an outcoupling element can be bonded to the optical fiber as an adhesive foil or arranged as a foil between the thermoplastic intermediate layer and the optical fiber, so that the outcoupling element is in direct contact with the optical fiber.

[0058] Mixtures of the aforementioned embodiments with regard to the coupling-out elements are also possible. For example, some of the coupling-out elements can be designed as foils and other coupling-out elements as laser structures, as described above.

[0059] "Transparent" in the sense of the invention means a light transmission (according to ISO 9050:2003) of at least 70%, preferably at least 80%, and particularly preferably at least 90%. "Semi-transparent" (according to ISO 9050:2003) in the sense of the invention means a light transmission of less than 70%, preferably at most 50%, and particularly preferably at most 5%. "Opaque" in the sense of the invention means a light transmission (according to ISO 9050:2003) of less than 5%, preferably less than 0.1%, in particular 0%.

[0060] When the laminated pane is used in glazing with coupled-in light, the decoupling elements appear as a luminous surface of the laminated pane. This can be used, for example, to illuminate an interior space and, in particular, to display symbols or patterns that serve to convey information or may be intended for purely aesthetic reasons. The decoupling elements allow for the realization of any shape or pattern.

[0061] If something is "based" on an inorganic material, it consists predominantly of this material, in particular essentially of this material, along with any impurities or dopants. Unless otherwise stated, the specified layer thickness or thicknesses refer to the geometric thickness of a layer. If something is "based" on a polymeric material, it consists predominantly of this material, i.e., at least 50%, preferably at least 60%, and in particular at least 70%. It may therefore also contain other materials such as stabilizers or plasticizers.

[0062] The invention also extends to a glazing comprising the composite pane according to the invention, a first light source for coupling light into the first optical waveguide and a second light source for coupling light into the second optical waveguide.

[0063] In a preferred embodiment of the invention, the composite pane also comprises at least the third optical waveguide, which is connected to the second optical waveguide via the third thermoplastic intermediate layer. The glazing then also comprises a third light source for coupling light into the third optical waveguide. The composite pane preferably also comprises at least the fourth optical waveguide, which is connected to the third optical waveguide via the fourth thermoplastic intermediate layer. The glazing then also comprises a fourth light source for coupling light into the fourth optical waveguide. Particularly preferably, in addition to the third and fourth optical waveguides, the composite pane also comprises the fifth optical waveguide, which is connected to the fourth optical waveguide via the fifth thermoplastic intermediate layer.The glazing then also includes a fifth light source for coupling light into the fifth optical fiber. Each optical fiber can thus be illuminated separately. The different light sources can, for example, emit light of different wavelengths, allowing the output coupling elements of the optical fibers to be illuminated in different colors.

[0064] When reference is made to "the light sources," this refers, unless explicitly stated otherwise, to all light sources in the glazing intended to couple light into the laminated pane. "The light sources" therefore include at least the first light source and the second light source, as well as, if present, the additional light sources (e.g., the third light source, the fourth light source, and the fifth light source) in the glazing.

[0065] The light sources are suitable for coupling light into the optical fibers. During operation, the light sources emit visible light, i.e., electromagnetic radiation in the visible spectral range, particularly in the range from 400 nm to 800 nm. Each light source can independently have one or more emission bands located in the visible spectral range and covering part of it. However, the light sources can also have a broad emission band that covers the entire visible spectral range. The emission band(s)—and thus the color of the emitted light—can be freely selected according to the requirements of the specific application.

[0066] Each light source preferably comprises at least one light-emitting diode (LED). Each light source can be a single light-emitting diode, but preferably it comprises an array of multiple light-emitting diodes. Said array is preferably installed in a common housing, for example as a linear array or a circular array in which the light-emitting diodes are arranged along a substantially straight line or a circular line. The electroluminescent material of the light-emitting diode can be, for example, an inorganic semiconductor or an organic semiconductor. In the latter case, it is also referred to as an organic light-emitting diode (OLED).

[0067] The plate-shaped optical fibers have a circumferential edge surface. The circumferential edge surface comprises an upper edge and a lower edge, as well as two side edges connecting the upper and lower edges. In the installed position, the upward-facing edge of the optical fiber is referred to as the upper edge, and the downward-facing edge is referred to as the lower edge. The edges running in between are referred to as side edges.

[0068] In a further preferred embodiment of the invention, at least the first light source is arranged on at least one section of a circumferential edge surface of the first optical waveguide. Alternatively or additionally, the second light source is preferably arranged on at least one section of a circumferential edge surface of the second optical waveguide. In particular, all light sources are arranged on at least one section of a circumferential edge surface of the optical waveguide for which they are intended for coupling light. The light sources are, for example, assigned to at least one lateral edge surface or attached to two opposite lateral edge surfaces and / or to the upper edge and / or the lower edge, for example glued or arranged in a holder fastened to the optical waveguide.The visible light is then coupled into the optical fiber via one, two, three, or four, or if available, more (e.g., all) edge surfaces. It may be advantageous to illuminate the optical fiber from one or more sides with multiple light sources to increase the illumination intensity and homogeneity accordingly.

[0069] In a further preferred embodiment of the invention, at least the first light source is arranged on the interior-side surface of the first optical waveguide and / or the second light source is arranged on the interior-side surface of the second optical waveguide. Alternatively, the first light source can also be arranged on the exterior surface of the first optical waveguide and / or the second light source can be arranged on the exterior surface of the second optical waveguide. In particular, all light sources are arranged on the interior-side surface or exterior surface of the optical waveguide assigned to them (i.e., the optical waveguide for which they are intended for light coupling). The light sources are preferably connected to the optical waveguide by means of an optically transparent adhesive. The light sources are preferably enclosed by the adjacent thermoplastic intermediate layer.This provides better protection for the light sources from external influences. Alternatively, the laminated pane can also have a recess in the area of ​​the light source.

[0070] In a preferred embodiment, the composite pane has the first partial region as described above, and the first light source is arranged in the first partial region on the interior-side surface of the first optical waveguide. If the composite pane also has the second partial region, the second light source is preferably arranged on the interior-side surface in the second partial region of the second optical waveguide. If, in addition, the composite pane also has the third partial region, the third light source is preferably arranged on the interior-side surface in the third partial region of the third optical waveguide. If, in addition, the composite pane also has the fourth partial region, the fourth light source is preferably arranged on the interior-side surface in the fourth partial region of the fourth optical waveguide.The exposed sections allow the light sources to be arranged more easily and effectively on the optical fibers, which simplifies the manufacturing process.

[0071] The optical fibers can be provided with a coupling element. The coupling element can be arranged between the optical fiber and the associated light source. Alternatively, the coupling element can also be located on the surface of the optical fiber facing away from the light source (for example, on the outside surface if the light source is arranged on the inside surface). The coupling element is arranged such that light emitted by the light source impinges on the coupling element and is then coupled into the respective optical fiber by reflection or light refraction at the coupling element.If the coupling means is arranged on the outer surface of the optical waveguide, the light from the light source arranged on the inner surface of the optical waveguide propagates at least through the respective optical waveguide before impinging on the coupling element. The light is predominantly reflected or diffracted by the coupling means, so that it is reradiated to the optical waveguide at an angle of incidence that is advantageous for coupling. The "relevant optical waveguide" refers to the optical waveguide that has the described coupling means.

[0072] For the purposes of the invention, "light source associated with the optical fiber" refers to the light source intended to couple light into the optical fiber. Thus, the first light source is associated with the first optical fiber, the second light source is associated with the second optical fiber, and so on.

[0073] In a preferred embodiment of the invention, a coupling means is applied to the outer surface of the first optical waveguide. The first light source is arranged on the inner surface of the first optical waveguide. Preferably, a further coupling means is applied to the outer surface of the second optical waveguide. The second light source is arranged on the inner surface of the second optical waveguide. Particularly preferably, a coupling means is applied to each optical waveguide on its outer surface. In this case, the light source assigned to the optical waveguide is arranged on the inner surface of the respective optical waveguide. The coupling means are preferably reflective structures.The reflective structures each have a plurality of inclined sections with a reflective surface and are configured such that the light radiated into the respective optical waveguide and passing through the optical waveguide is reflected by the reflective surface of the inclined sections and at least partially reradiated into the respective optical waveguide. Each reflective structure is preferably provided with a reflective coating, which is responsible for the reflective properties of the reflective structure. The reflective coating comprises at least one reflective layer based on a metal or a metal alloy. This increases the reflectivity of the reflective coating.

[0074] The reflective structures are particularly preferably microprism films. Each microprism film is applied, for example, glued, to the outer surface of the respective optical waveguide. The reflective surface of the reflective structure is preferably arranged facing away from the respective optical waveguide. The microprism film is transparent except for the reflective surface. The light from the light source associated with the optical waveguide exits the optical waveguide via the outer surface after entering the optical waveguide, passes through the microprism film, and strikes its reflective surface, where it is reflected and passes through the microprism film again, re-entering the optical waveguide via the outer surface.

[0075] The reflective surface of the reflective structure has sections that are inclined relative to the optical waveguide to which it is applied. This means that the sections are not arranged parallel to the outer surface of the optical waveguide, but at an angle greater than 0° to the surface. Said sections have an angle to the outer surface that is between 0° and 90°, preferably from 28° to 60° or from 30° to 60°, very particularly preferably from 30° to 50°, in particular from 40° to 50°, for example approximately 45°. This refers to the absolute value of the respective angle. The sections can be inclined in different directions. The sections are preferably also inclined relative to one another. This means that adjacent sections are inclined relative to one another, i.e., are not parallel, but rather arranged at an angle between 0° and 180° to one another.Said sections of the reflective structure are preferably substantially planar. The inclination of the sections of the reflective structure relative to the outer surface of the optical waveguide on which the reflective structure is applied determines the angle at which the reflected light is reflected back into the optical waveguide.

[0076] In an alternative, particularly preferred embodiment, the coupling element is applied to the interior-side surface of the first optical waveguide. The beam path of the first light source is directed toward the coupling means. The coupling means couples the light arriving from the light source into the respective optical waveguide, preferably by refraction. The coupling means is therefore a light-refracting structure. The first light source is preferably connected to the respective optical waveguide via the coupling means. A collimator can be arranged between the first light source and the coupling means, i.e., in the beam path of the light source. Preferably, each optical waveguide has such a coupling element on its interior-side surface, and each light source assigned to the optical waveguide is connected to the respective optical waveguide via the coupling means of the respective optical waveguide.

[0077] Regardless of whether the coupling means is arranged between the respective optical waveguide and its associated light source or on the outer surface of the respective optical waveguide, the coupling means of each optical waveguide is preferably arranged, if present, in one of the exposed subregions of the optical waveguide. This means, for example, that the coupling means of the first optical waveguide is preferably arranged in the first subregion of the first optical waveguide, the coupling means of the second optical waveguide is preferably arranged in the second subregion of the second optical waveguide, and the coupling means of the third optical waveguide is preferably arranged in the third subregion of the third optical waveguide, and so on.In the case of an optical waveguide in which the interior surface is exposed, i.e. exposed to the interior, the coupling element is preferably arranged in the edge region of the optical waveguide.

[0078] In a preferred embodiment of the invention, at least the first light source and the second light source are arranged on or in a light-guiding element. Preferably, all light sources are arranged on or in a light-guiding element. Preferably, each light source is arranged in or on a light-guiding element separate from the other light-guiding elements. Each light-guiding element is arranged on the interior-side surface of the optical waveguide to which the respective light source is assigned, and has a light output surface facing this optical waveguide. The light-guiding element preferably comprises a body made of an optically transparent, cured adhesive. The light generated by the light source is provided for coupling into the optical waveguide assigned to it via the light output surface.The refractive index of the optically transparent, cured adhesive differs by a maximum of 0.05, preferably a maximum of 0.01, from the refractive index of the optical fiber on which it is arranged. This allows the light to be coupled into the optical fiber with little or no loss of light intensity. The light is transmitted almost entirely at the transition from the light-guiding element to the optical fiber and is largely neither refracted nor reflected. The light source assigned to the optical fiber is arranged in particular in or on the light-guiding element in such a way that the light emitted by it strikes the optical fiber at a suitable angle of incidence, so that the light is coupled in and propagates in the optical fiber.In other words, the light emitting surface of each light source is arranged at an angle to its associated optical fiber that is greater than the critical angle of the optical fiber on its outer surface.

[0079] In a further embodiment, the light-guiding element has a light-reflecting coating on an outer surface, which is suitable for reflecting the light emitted by the light source toward the light output surface. This prevents the light from escaping from the light-guiding element and enhances the light transmission.

[0080] The light-guiding element preferably comprises a housing having an opening at the light exit surface. The housing can be a hollow body filled with the optically transparent, cured adhesive, wherein the hollow body is formed from a thermally dimensionally stable material, in particular plastic, metal, or aluminum. Furthermore, the housing can have two sides arranged opposite the light exit surface, wherein the two sides define the hollow body with the opening.

[0081] Curable, optically transparent adhesives can be irreversibly cured. Typically, they are plastics that undergo polymer-crosslinking through curing. This distinguishes them significantly from thermoplastics, which are also optically transparent but can be reversibly softened by the application of heat. In contrast, curable adhesives cannot be returned to a flowable state once they have cured. Therefore, optically transparent, curable adhesives are not non-curable thermoplastics. Curable, optically transparent adhesives can be cured by heat, exposure to electromagnetic radiation, preferably UV radiation, and / or chemically. Curing is preferably achieved by applying heat or increasing the temperature and / or UV radiation.

[0082] The transparent adhesive, for example, is based on silicone. Optically transparent adhesives are known, in particular, by the acronym LOCA (liquid optically clear adhesive). These are often used in touch-sensitive displays, for example, to firmly bond them to an LCD or to firmly bond plastic covers to the touch-sensitive displays. After application, the LOCA is often cured using UV radiation.

[0083] The curable, optically transparent adhesive can, for example, contain or consist of polyurethane (PU), polyacrylate, polyacetate resin, casting resin, epoxy resin, acrylate, or a copolymer or mixture thereof. The optically transparent adhesive is advantageously made of a casting resin, particularly polyurethane- or silicone-based. The housing of the light module can serve as a mold for the curable, optically transparent adhesive.

[0084] In a further embodiment of the glazing arrangement according to the invention, each light-guiding element is firmly bonded to the optical waveguide, which is associated with the light source arranged in or on the light-guiding element, by means of the optically transparent, cured adhesive. In other words, each light-guiding element is bonded to the optical waveguide, which is associated with the light source arranged in or on the light-guiding element. Alternatively, the light-guiding element can be firmly bonded to the optical waveguide, which is associated with the light source arranged in or on the light-guiding element, by means of an adhesive tape. For this purpose, the adhesive tape has the optically transparent adhesive on two sides.

[0085] Optionally, each light source can independently have a collimator arranged between the optical waveguide assigned to the light source and the light source, wherein the collimator is located in the beam path of the respective light source. Preferably, at least the first light source and the second light source have such a collimator. In particular, all light sources have such a collimator. The collimator is arranged between the light source and the associated optical waveguide so that the light is coupled into the optical waveguide via the collimator. The collimator generates from the typically divergent light beam of the light source a light beam with preferably an essentially parallel beam path, but at least a less divergent, i.e. more concentrated beam path. The beam cone of the light source is therefore narrowed by the collimator.This has the advantage that the entire light beam is irradiated into the composite pane at the same angle of incidence. Especially if at least one of the optical fibers is equipped with a reflective structure, such a substantially convergent angle of incidence allows a large portion of the light to be coupled into the optical fiber via the reflective structure, resulting in total internal reflection. This optimizes the light yield.

[0086] In the simplest case, the collimator is a type of converging lens, with the light source preferably positioned at its focal point. The collimator can be made of glass or a transparent plastic, for example, in particular polycarbonate (PC) or polymethyl methacrylate (PMMA). If the light source is designed as an array of multiple LEDs, a separate collimator can be provided for each LED. However, a common collimator is preferably used for the entire LED array. In the case of a linear LED array, a rod-like collimator can be used, for example, whose length corresponds at least to the length of the LED array.

[0087] The various embodiments of the invention can be implemented individually or in any combination.

[0088] The composite pane can be manufactured using the following process:

[0089] (A) providing a layer stack comprising, in this order, the outer pane, the first thermoplastic intermediate layer, the first optical waveguide, the second thermoplastic intermediate layer and the second optical waveguide, and

[0090] (B) Lamination of the layer stack to form the composite pane.

[0091] The laminated pane can be produced using known lamination processes, for example autoclave processes, vacuum bag processes, vacuum ring processes, calender processes, vacuum laminators, or combinations thereof. The bonding of the outer pane and the optical fibers is usually carried out under the influence of heat, vacuum, and / or pressure. The laminated pane is intended to be a component of a glazing unit. The laminated pane or glazing unit can be used as a window pane in a vehicle. A particularly preferred use is a vehicle roof pane that can be illuminated in three dimensions. The vehicle can in principle be any land vehicle, watercraft, or aircraft, and is preferably a passenger car, truck, or rail vehicle.The laminated glass or glazing can also be used in buildings. For example, the laminated glass can be used as a window pane, glass facade, or glass door, either indoors or outdoors, particularly as a window pane in a building or an interior. The laminated glass or glazing can also be used as a component of furniture, electrical appliances, as a component of furnishings, or as a furnishing item.

[0092] The invention is explained in more detail below with reference to figures and exemplary embodiments. The figures shown are schematic representations and not to scale. The figures shown do not limit the invention in any way.

[0093] They show:

[0094] Fig. 1a is a plan view of an embodiment of a glazing according to the invention, Fig. 1b is a cross-sectional view of the glazing shown in Figure 1a,

[0095] Fig. 1c an enlarged edge area in the cross-sectional view from Fig. 1b,

[0096] Fig. 1d is an enlarged central region of the composite pane according to the invention in the cross-sectional view from Fig. 1b,

[0097] Fig. 2a is a cross-sectional view of an alternative embodiment of a glazing according to the invention,

[0098] Fig. 2b an enlarged edge area in the cross-sectional view from Fig. 2a,

[0099] Fig. 3a is a plan view of a further embodiment of an inventive

[0100] Glazing and

[0101] Fig. 3b is an enlarged plan view of an edge area of ​​the glazing from Fig. 3a.

[0102] Figures 1a to 1d each show different aspects of a first embodiment of the glazing 101 according to the invention. Figure 1a shows a plan view of a glazing 101. Figure 1b shows a cross-sectional view of the glazing 101 shown in plan view from Figure 1a. The section line for the cross section is indicated in Figure 1a by a dashed line XX'. Figure 1c shows an enlarged section Z1 of an edge region of the glazing 101. The section Z1 is indicated in Figure 1b by a circular dashed line. Figure 1d shows an enlarged section Z2 of a central region of the laminated pane 100 of the glazing 101. The section Z2 is indicated in Figure 1b by a circular dashed line.

[0103] The composite pane 100 of the glazing 101 is designed, for example, as a roof pane of a vehicle, in particular a passenger car. For the sake of simplicity, it is shown flat, although such vehicle roof panes are typically curved. The composite pane 100 is structurally formed from an outer pane 1, a first thermoplastic intermediate layer 3.1, a first optical waveguide 2.1, a second thermoplastic intermediate layer 3.2, and a second optical waveguide 2.2. The outer pane 1 has an outer surface I facing the outside environment and an interior surface II facing the vehicle interior. The first optical waveguide 2.1 has an outer surface III facing the outside environment and an interior surface IV facing the vehicle interior. The second optical waveguide 2.2 has an exterior surface V, which faces the external environment, and an interior surface VI, which faces the vehicle interior. The first thermoplastic intermediate layer 3.1 is arranged between the first optical waveguide 2.1 and the outer pane 1, firmly bonding them together. The second thermoplastic intermediate layer 3.2 is arranged between the first optical waveguide 2.1 and the second optical waveguide 2.2, firmly bonding them together.

[0104] The outer pane 1 is made, for example, of soda-lime glass and has a thickness of, for example, 2.1 mm each. The optical waveguides 2.1, 2.2 are made, for example, of soda-lime glass and each have a thickness of 500 μm. A frame-shaped masking region 8 is arranged in the edge region of the composite pane 100. The masking region 8 is formed, for example, by a black enamel on the interior-side surface II of the outer pane 1. The thermoplastic intermediate layers 3.1, 3.2 are formed, for example, on the basis of PVB and are, for example, each 0.3 mm thick.

[0105] In a region of the composite pane 100 intended for viewing, also called the central region, outcoupling elements 4 are arranged in the optical waveguides 2.1, 2.2 (see Fig. 1d). In a plan view of the composite pane 100, the outcoupling elements 4 form the word "Saint-Gobain" when illuminated. The outcoupling elements 4 are arranged partly within the first optical waveguide 2.1 and partly within the second optical waveguide 2.2. The outcoupling elements 4 are incorporated into the optical waveguides 2.1, 2.2, for example, by laser structuring.

[0106] The glazing 101 also comprises a first light source 7.1 and a second light source 7.2. The first light source 7.1 is arranged relative to the first optical waveguide 2.1 such that the light 5 emitted by the first light source 7.1 is coupled into the first optical waveguide 2.1. The second light source 7.2 is arranged relative to the second optical waveguide 2.2 such that the light 5 emitted by the second light source 7.2 is coupled into the second optical waveguide 2.2. The first light source 7.1 is arranged in a section of the circumferential edge surface U of the first optical waveguide 2.1. The second light source 7.2 is arranged in a section of the circumferential edge surface U of the second optical waveguide 2.2. The light sources 7.1, 7.2 couple light 5 into the optical waveguide 2.1, 2.2 via the respective edge surface U. The first light source 7.1 and the second light source 7.2 are linear andare strip-shaped and extend along an edge section of the composite pane 100. The light sources 7.1, 7.2 are, for example, a linear arrangement of LEDs (light-emitting diodes). The light 5 emitted by the light sources 7.1, 7.2 can be of different colors. For example, the first light source 7.1 emits light 5 in a wavelength range from 500 nm to 510 nm, and the second light source 7.2 emits light 5 in a wavelength range from 700 nm to 710 nm. The outer pane 1 can also be designed such that it extends slightly beyond the surface of the optical waveguides 2.1, 2.2, for example, so far that it conceals the light sources 7.1, 7.2 when viewed through the composite pane 1 (not shown here). In other words: the light sources 7.1, 7.2 are in overlap with the outer pane 1.

[0107] The arrangement of the outcoupling means 4 in different planes creates a three-dimensional illumination impression for the observer. A further advantage is that the areas of the optical waveguides 2.1, 2.2 that are provided with outcoupling elements 4 can be kept relatively small, since the outcoupling elements 4 are distributed across different optical waveguides 2.1, 2.2. Due to the small thickness of the optical waveguides 2.1, 2.2, the stability of the composite pane 100 is largely unaffected by the multiple lamination.

[0108] The variant shown in Figures 2a and 2b essentially corresponds to the variant from Figures 1a to 1d, so that only the differences will be discussed here, and otherwise reference is made to the description of Figures 1a to 1d. Figures 2a and 2b each show different aspects of a second embodiment of the glazing 101 according to the invention. Figure 2a shows a cross-sectional view of the glazing 101. Figure 2b shows an enlarged section Z3 of an edge region of the glazing 101. The section Z3 is indicated in Figure 2a by a circular dashed line.

[0109] In addition to the first optical waveguide 2.1 and the second optical waveguide 2.2, the composite pane 100 also comprises a third optical waveguide 2.3, which is connected to the second optical waveguide 2.2 via a third thermoplastic intermediate layer 3.3. Furthermore, the composite pane 100 also comprises a fourth optical waveguide 2.4, which is connected to the third optical waveguide 2.3 via a fourth thermoplastic intermediate layer 3.4. The optical waveguides 2.1, 2.2, 2.3, 2.4 are made, for example, of soda-lime glass and each have a thickness of 500 μm. The thermoplastic intermediate layers 3.1,

[0110] 3.2, 3.3, 3.4 are formed, for example, from PVB and are each 0.3 mm thick, for example. The third optical waveguide 2.3 has an outer surface VII, which faces the external environment, and an interior surface VIII, which faces the vehicle interior. The fourth optical waveguide 2.4 has an outer surface IX, which faces the external environment, and an interior surface X, which faces the vehicle interior.

[0111] The first thermoplastic intermediate layer 3.1, for example, is tinted and has a light transmittance of less than 10%. The layer thickness of the thermoplastic intermediate layer 3.1 is, for example, 0.3 mm.

[0112] In contrast to the design of Figures 1a to 1d, the optical fibers 2.1, 2.2,

[0113] 2.3, 2.4 here have a low-refractive-index coating 6 applied to their outer surface III, V, VII, IX. The low-refractive-index coating 6 extends over the entire outer surface III, V, VII, IX of each optical waveguide 2.1, 2.2, 2.3,

[0114] 2.4, The first optical waveguide 2.1, the second optical waveguide 2.2, and the third optical waveguide 2.3 additionally have a low-refractive-index coating 6 on their interior-side surfaces IV, VI, VIII. The low-refractive-index coatings 6 are formed, for example, as a polymer matrix of polyacrylate, with silicon dioxide-based particles embedded in the polymer matrix, and each have a layer thickness of 0.5 μm. The low-refractive-index coating 6 on the interior-side surface IV of the first optical waveguide 2.1 extends over the entire interior-side surface IV of the first optical waveguide 2.1 with the exception of a first partial region A. The second thermoplastic intermediate layer 3.2 and the second optical waveguide 2.2 also extend over the entire interior-side surface IV of the first optical waveguide 2.1 with the exception of the first partial region A.The low-refractive-index coating 6 on the interior-side surface VI of the second optical waveguide 2.2 extends over the entire interior-side surface VI of the second optical waveguide 2.2 with the exception of a second partial region B. The third thermoplastic intermediate layer 3.3 and the third optical waveguide 2.3 also extend over the entire interior-side surface VI of the second optical waveguide 2.2 with the exception of the second partial region B. The low-refractive-index coating 6 on the interior-side surface VIII of the third optical waveguide 2.3 extends over the entire interior-side surface VIII of the third optical waveguide 2.3 with the exception of a third partial region C. The fourth thermoplastic intermediate layer 3.4 and the fourth optical waveguide 2.4 also extend over the entire interior-side surface VIII of the third optical waveguide 2.3 with the exception of the third partial region C.The first optical waveguide 2.1, the second optical waveguide 2.2, and the third optical waveguide 2.3 each have an exposed partial region A, B, C on their interior-side surfaces IV, VI, VIII. A light source 7.1, 7.2, 7.3 is arranged in each of these partial regions A, B, C. A fourth light source 7.4 is arranged in an edge region on the interior-side surface X of the fourth optical waveguide 7.4.

[0115] The light sources 7.1, 7.2, 7.3, 7.4 are each arranged on a light-guiding element 9 and connected via the light-guiding element 9 to the corresponding optical waveguide 2.1, 2.2, 2.3, 2.4, into which the light 5 emitted by them is coupled. Preferably, the light sources 7.1, 7.2, 7.3, 7.4 and the light-guiding elements 9 are cast or glued to form a flush frame in order to obtain a flush installation edge of the composite pane 100. The light sources 7.1, 7.2, 7.3, 7.4 are arranged on the light-guiding element 9 such that the light 5 emitted by them strikes the optical waveguide 2.1, 2.2, 2.3, 2.4—on which they are arranged—at an angle of incidence suitable for coupling and then propagates through the effect of total internal reflection in the respective optical waveguide 2.1, 2.2, 2.3, 2.4. The light-guiding elements 9 are made, for example, of cured plastic, which has a refractive index similar to soda-lime glass.The light 5 emitted by the light sources 7.1, 7.2, 7.3, 7.4 can be of different colors. The output coupling elements 4 are not located within the optical waveguides 2.1, 2.2, 2.3, 2.4, but rather are applied to the interior surfaces IV, VI, VIII, X of the optical waveguides 2.1, 2.2, 2.3, 2.4, i.e., printed. The low-refractive-index coating 6 is not present in the areas of the optical waveguides 2.1, 2.2, 2.3, 2.4 that are provided with a print 6.

[0116] The variant shown in Figures 3a and 3b essentially corresponds to the variant in Figures 2a and 2b, so that only the differences are discussed here and otherwise reference is made to the description of Figures 2a and 2b or 1a to 1d.

[0117] Figure 3a shows a plan view of a further embodiment of the glazing 101 according to the invention. Figure 3b shows an enlarged section Z4 of an edge region of the glazing 101 in plan view. Section Z4 is indicated in Figure 3a by a circular dashed line.

[0118] In the variant shown here, the light sources 7.1, 7.2, 7.3, 7.4 are not strip-shaped, but point-shaped. The first optical waveguide 2.1, the second optical waveguide 2.2, and the third optical waveguide 2.3 also have exposed partial regions A, B, C in this embodiment. The partial regions A, B, C of the optical waveguides 2.1, 2.2, 2.3 do not extend in a strip-like manner along an edge of the composite pane 100, but are arranged next to one another in a square and all border on the edge of the composite pane 100. This arrangement of the light sources 7.1, 7.2, 7.3, 7.4 reduces the space required in the edge region of the pane 100. The low-refractive-index coatings 6 are not shown in Fig. 3b for the sake of clarity.

[0119] List of reference symbols

[0120] 1 outer pane

[0121] 2.1 first plate-shaped optical fiber

[0122] 2.2 second plate-shaped optical fiber

[0123] 2.3 third plate-shaped optical fiber

[0124] 2.4 fourth plate-shaped optical fiber

[0125] 3.1 first thermoplastic intermediate layer

[0126] 3.2 second thermoplastic intermediate layer

[0127] 3.3 third thermoplastic intermediate layer

[0128] 3.4 fourth thermoplastic intermediate layer

[0129] 4 Decoupling element

[0130] 5 light

[0131] 6 low-refractive index coating

[0132] 7.1 first light source

[0133] 7.2 second light source

[0134] 7.3 third light source

[0135] 7.4 fourth light source

[0136] 8 Masking area

[0137] 9 Light guide element

[0138] 100 composite panes

[0139] 101 Glazing

[0140] I outside surface of the outer pane 1

[0141] II Interior surface of the outer pane 1

[0142] III outer surface of the first optical fiber 2.1

[0143] IV Interior surface of the first optical fiber 2.1

[0144] V outer surface of the second optical fiber 2.2

[0145] VI interior surface of the second optical fiber 2.2

[0146] VII outer surface of the third optical fiber 2.3

[0147] VIII interior surface of the third optical fiber 2.3

[0148] IX outer surface of the fourth optical fiber 2.4

[0149] X Interior surface of the fourth optical fiber 2.4

[0150] U Edge surface of the optical fibers

[0151] A first section of the first optical fiber 2.1 B second section of the second optical fiber 2.2

[0152] C third section of the third optical fiber 2.3

[0153] Z1 enlarged edge area of ​​glazing 101 from Figure 1b

[0154] Z2 enlarged view area of ​​the laminated pane 100 from Figure 1b Z3 enlarged edge area of ​​the glazing 101 from Figure 2a

[0155] Z4 enlarged edge area of ​​glazing 101 from Figure 3a

[0156] XX' cutting line

Claims

Patent claims 1. A composite pane (100) for an illuminable glazing (101), comprising at least an outer pane (1), a first plate-shaped optical waveguide (2.1) with at least one outcoupling element (4) for coupling out light (5), and a second plate-shaped optical waveguide (2.2) with at least one outcoupling element (4) for coupling out light (5), wherein a first thermoplastic intermediate layer (3.1) is arranged between the outer pane (1) and the first optical waveguide (2.1), and a second thermoplastic intermediate layer (3.2) is arranged between the first optical waveguide (2.1) and the second optical waveguide (2.2), wherein the first optical waveguide (2.1) and the second optical waveguide (2.2) each have a thickness of at most 700 pm.

2. Composite pane (100) according to claim 1, wherein the second optical waveguide (2.2) and the second thermoplastic intermediate layer (3.2) extend over the entire surface of the first optical waveguide (2.1) with the exception of a first partial region (A).

3. Composite pane (100) according to claim 1 or 2, wherein the first optical waveguide (2.1) and the second optical waveguide (2.2) are formed on the basis of mineral glass, polycarbonate or polymethyl methacrylate.

4. Composite pane (100) according to one of claims 1 to 3, wherein a low-refractive-index coating (6) is applied to at least one of the surfaces (III, IV) of the first optical waveguide (2.1) and / or to at least one of the surfaces (V, VI) of the second optical waveguide (2.2), which coating has a refractive index which is at least 0.05 lower than the refractive index of the optical waveguide (2.1, 2.2) to which it is applied.

5. Composite pane (100) according to claim 4, wherein the low-refractive coating (6) contains or consists of silicon oxide.

6. Composite pane (100) according to one of claims 1 to 5, wherein the first thermoplastic intermediate layer (3.1) and the second thermoplastic Intermediate layer (3.2) based on polyvinyl butyral, polyurethane, polyvinyl acetate or polyester, preferably polyvinyl butyral.

7. Composite pane (100) according to one of claims 1 to 6, further comprising a third plate-shaped optical waveguide (2.3) with at least one coupling-out element (4) for coupling out light (5), which is connected to the second optical waveguide (2.2) via a third thermoplastic intermediate layer (3.3), and wherein the third optical waveguide (2.3) has a thickness of at most 700 pm.

8. Composite pane (100) according to claim 7, further comprising a fourth plate-shaped optical waveguide (2.4) with at least one coupling-out element (4) for coupling out light (5), which is connected to the third optical waveguide (2.3) via a fourth thermoplastic intermediate layer (3.4), and wherein the fourth optical waveguide (2.4) has a thickness of at most 700 pm.

9. Composite pane (100) according to one of claims 1 to 8, wherein the first thermoplastic intermediate layer (3.1) is tinted with a light transmittance of maximum 30%, preferably maximum 10%.

10. Composite pane (100) according to one of claims 1 to 9, wherein the coupling-out elements (4) are arranged within the respective optical waveguide (2.1, 2.2, 2.3, 2.4) and are formed by means of laser structuring.

11. Composite pane (100) according to one of claims 1 to 10, wherein at least the first optical waveguide (2.1) and the second optical waveguide (2.2) each have a thickness of 200 pm to 500 pm.

12. Illuminable glazing (101), comprising at least one composite pane (100) according to one of claims 1 to 11, a first light source (7.1) for coupling light (5) into the first optical waveguide (2.1) and a second light source (7.2) for coupling light (5) into the second optical waveguide (2.2).

13. Glazing (101) according to claim 12, wherein the first light source (7.1) is arranged on at least a portion of a circumferential edge surface (U) of the first optical waveguide (2.1) and the second light source (7.2) is arranged on at least a portion of a circumferential edge surface (II) of the second optical waveguide (2.2).

14. Glazing (101) according to claim 12, wherein the first light source (7.1) is arranged on an interior-side surface facing the second thermoplastic intermediate layer (3.2). Surface (IV) of the first optical waveguide (2.1) and the second light source (7.2) is arranged on an interior-side surface (VI) of the second optical waveguide (2.2) facing away from the second thermoplastic intermediate layer (3.2).

15. Glazing (101) according to claim 14, wherein the second optical waveguide (2.2) and the second thermoplastic intermediate layer (3.2) extend over the entire surface of the first optical waveguide (2.1) with the exception of a first partial region (A), and the first light source (7.1) is arranged on the first optical waveguide (2.1) in the first partial region (A).

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